[Ventricular arrhythmias of catecholaminergic origin and sudden death].
The hereditary disease known as polymorphic catecholaminergic ventricular tachycardia (PCVT) is highly lethal. Almost 30% of the affected patients die before 40 years old, mainly due to sudden cardiac death. We have used isolated hearts from mutant mice (type 2 ryanodine receptors, RyR2/RyR2(R4496C)) to investigate arrhythmia mechanisms that are adrenergic- and intracellular calcium ([Ca2+]o) levels-dependent. Our results corroborate that polymorphic and bidirectional ventricular arrhythmias, as well as ventricular fibrillation, occurs in 50% of RyR2/ RyR2(R4496C) mice, and in less than 12% of the non-affected mice. Our hypothesis suggests that the origin of catecholaminergic arrhythmias in animals, and possibly in humans, is conditioned by the focal activity that begins by late post-potentials in the Purkinje fibers.
Jalife
José
J
Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY 13210, USA. jalifej@upstate.edu
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000503:physiopathology; D016757:Death, Sudden, Cardiac / Q000209:etiology*; D006352:Heart Ventricles; D051379:Mice; D011690:Purkinje Fibers / Q000503:physiopathology; D017983:Receptors, Catecholamine / Q000502:physiology*
D017983:Receptors, Catecholamine